Fixes for re-enabling more MSVC level 4 warnings: chrome/browser/ edition

chrome/browser/history/history_backend.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/history/history_backend.h"
 
 #include <algorithm>
 #include <functional>
 #include <list>
 #include <map>
@@ skipping 331 matching lines @@
   // http://crbug.com/96860 is fixed.
   if ((t == content::PAGE_TRANSITION_TYPED ||
        t == content::PAGE_TRANSITION_AUTO_BOOKMARK) &&
       (transition_type & content::PAGE_TRANSITION_FORWARD_BACK) == 0) {
     // If so, create or get the segment.
     std::string segment_name = db_->ComputeSegmentName(url);
     URLID url_id = db_->GetRowForURL(url, NULL);
     if (!url_id)
       return 0;
 
-    if (!(segment_id = db_->GetSegmentNamed(segment_name))) {
-      if (!(segment_id = db_->CreateSegment(url_id, segment_name))) {
+    segment_id = db_->GetSegmentNamed(segment_name);
+    if (!segment_id) {
+      segment_id = db_->CreateSegment(url_id, segment_name);
+      if (!segment_id) {
         NOTREACHED();
         return 0;
       }
     } else {
       // Note: if we update an existing segment, we update the url used to
       // represent that segment in order to minimize stale most visited
       // images.
       db_->UpdateSegmentRepresentationURL(segment_id, url_id);
     }
   } else {
     // Note: it is possible there is no segment ID set for this visit chain.
     // This can happen if the initial navigation wasn't AUTO_BOOKMARK or
     // TYPED. (For example GENERATED). In this case this visit doesn't count
     // toward any segment.
-    if (!(segment_id = GetLastSegmentID(from_visit)))
+    segment_id = GetLastSegmentID(from_visit);
+    if (!segment_id)
       return 0;
   }
 
   // Set the segment in the visit.
   if (!db_->SetSegmentID(visit_id, segment_id)) {
     NOTREACHED();
     return 0;
   }
 
   // Finally, increase the counter for that segment / day.
@@ skipping 2364 matching lines @@
   int rank = kPageVisitStatsMaxTopSites;
   std::map<GURL, int>::const_iterator it = most_visited_urls_map_.find(url);
   if (it != most_visited_urls_map_.end())
     rank = (*it).second;
   UMA_HISTOGRAM_ENUMERATION("History.TopSitesVisitsByRank",
                             rank, kPageVisitStatsMaxTopSites + 1);
 }
 #endif
 
 }  // namespace history